From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C4936C28EBD for ; Sun, 9 Jun 2019 17:01:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9AF0C212F5 for ; Sun, 9 Jun 2019 17:01:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560099710; bh=zabL5YfqfgkOhrTRcXafw5T08OQA8mRkWoJ70DYQGDc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=faev/K1I3GeW/AhZEAaQ7gXqqYtKdpuZobj/dEUHnkYem+IAoeCoChyBuGgERCqOv rEa22xflGOvu4J3Ei+aLZvD2L4DPHmdFbL8hRlErxv8C0yqtzFzTgKaNtldrSFHEZj E38rwyAj+8c1E7MoA7z95+0eDY6lNFgsflVgtqAs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388138AbfFIRBs (ORCPT ); Sun, 9 Jun 2019 13:01:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:39222 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388124AbfFIRBp (ORCPT ); Sun, 9 Jun 2019 13:01:45 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0F2E1207E0; Sun, 9 Jun 2019 17:01:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560099704; bh=zabL5YfqfgkOhrTRcXafw5T08OQA8mRkWoJ70DYQGDc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kE5D3TfyrsAqYY1oJtbF7qFJG7fx+Lw49/Ayb1jHMZesVcwT+eW34MyBu+Yd0bt5i h8Dj9EJRxIP2gdA6NbAabGULto4g98alzf7VbPffvfIHo0scKm2mlbjqV1usjc+kkI EaSArS0lP7XoXAoq4F6eHvoNK87eck+aCJDT8t7o= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kefeng Wang , John Garry , Guenter Roeck , Sasha Levin Subject: [PATCH 4.4 134/241] hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses Date: Sun, 9 Jun 2019 18:41:16 +0200 Message-Id: <20190609164151.662324680@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190609164147.729157653@linuxfoundation.org> References: <20190609164147.729157653@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit 8c0826756744c0ac1df600a5e4cca1a341b13101 ] Super-IO accesses may fail on a system with no or unmapped LPC bus. Also, other drivers may attempt to access the LPC bus at the same time, resulting in undefined behavior. Use request_muxed_region() to ensure that IO access on the requested address space is supported, and to ensure that access by multiple drivers is synchronized. Fixes: 8d5d45fb1468 ("I2C: Move hwmon drivers (2/3)") Reported-by: Kefeng Wang Reported-by: John Garry Cc: John Garry Acked-by: John Garry Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/smsc47b397.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/hwmon/smsc47b397.c b/drivers/hwmon/smsc47b397.c index 6bd2007565603..cbdb5c4991ae3 100644 --- a/drivers/hwmon/smsc47b397.c +++ b/drivers/hwmon/smsc47b397.c @@ -72,14 +72,19 @@ static inline void superio_select(int ld) superio_outb(0x07, ld); } -static inline void superio_enter(void) +static inline int superio_enter(void) { + if (!request_muxed_region(REG, 2, DRVNAME)) + return -EBUSY; + outb(0x55, REG); + return 0; } static inline void superio_exit(void) { outb(0xAA, REG); + release_region(REG, 2); } #define SUPERIO_REG_DEVID 0x20 @@ -300,8 +305,12 @@ static int __init smsc47b397_find(void) u8 id, rev; char *name; unsigned short addr; + int err; + + err = superio_enter(); + if (err) + return err; - superio_enter(); id = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID); switch (id) { -- 2.20.1